1. Field of the Invention
The present invention relates to power management of an electronic system. More particularly, the present invention relates to a power scaling unit and its power scaling modules of an electronic system.
2. Description of the Related Art
Power scaling is the procedure to change computation power consumed by an electronic system by changing operating frequency or operating voltage of the components of the electronic system. Power scaling is for trading off of performance/feature and power consumption. Data-processing electronic systems, such as personal computers, are becoming more complex in design and architecture, while expected power consumption of such electronic systems is getting lower. Consequently, power management of electronic systems is getting more complex and more demanding as well.
In such a trend, power scaling has to be used strictly and smartly. Nowadays an electronic system may include multiple power domains. Each power domain may be driven by different operating frequencies and/or operating voltages. The electronic device may execute several applications at the same time. Ideally, each of the applications has a corresponding power profile recording the power scaling applied to the power domains when the particular application is running. When the applications go through context switch, their power profiles have to be switched as well. The switching of power profiles may cause extensive change of power scaling conditions across the power domains. In such an electronic system, there is a need for a scalable power scaling mechanism which provides fine-grained power control and smooth transition of power states in the entire electronic system according to application activities.